1. Field of the Invention
The present invention pertains to an apparatus and method for endoscopic and open surgery and, more particularly, to a surgical device incorporating a rigid endoscopic instrument and methods of manipulating the endoscope.
2. Discussion of the Prior Art
Various procedures are accomplished in both open surgery and endoscopic surgery, and generally, the procedures include multiple steps and require various operating instruments. "Open surgery" refers to surgery wherein the surgeon gains access to the surgical site by a relatively large incision and "endoscopic surgery" refers to minimally invasive surgery wherein the surgeon gains access to the surgical site via one or more portals through which endoscopes are introduced to view the surgical site and through which instruments having "end effectors", such as forceps, cutters, needle holders, cauterizers, and the like, are introduced to the surgical site.
The performance of an endoscopic procedure typically involves creation of one or more puncture sites through a wall of an anatomical cavity using a penetrating instrument including an obturator, such as a trocar, disposed within a portal sleeve. After the penetrating instrument has penetrated into the anatomical cavity, the obturator is withdrawn, leaving the sleeve in place to form a portal in the cavity wall for the introduction of instruments such an endoscopes, scissors, forceps, needle holders and the like, into the anatomical cavity.
The various end effectors at the distal end of the instrument are manipulated by the surgeon using controls disposed at the proximal end of the instrument. Of course, it is desirable to move the end effectors through various paths, depending on the step being performed. Traditionally, this was accomplished by moving the entire end of the endoscopic instrument. Recently, however, it has been proposed to provide a plurality of end effectors on a single endoscopic instrument to be passed through a single portal for minimizing the number of puncture sites and thus reducing the risk and the healing time associated with endoscopic surgery.
When a plurality of end effectors are incorporated into a single endoscopic device, it is desirable to move the end effectors individually with respect to one another without necessarily moving the entire device. Also, even in single end effector devices, it is often desirable to move the end effector through a predetermined path, such as an arc, during an operative step, without repositioning the entire endoscopic device.
Of course, it is also generally desirable to minimize the size of each puncture site. Further, in order to permit operations on a wide range of tissue sizes, it is desirable to provide a wide range of relative movement between the end effectors. The objectives, minimal number of punctures, small size punctures and wide range of relative movement, are seemingly contradictory and so conventional devices of the prior art have not achieved them.
In particular, U.S. Pat. No. 5,582,617 discloses an endoscopic instrument having an end effector movable from a position within the diameter of the barrel of the device to a position outside the diameter. However, this device must pivot about a first axis transverse to the axis of the barrel as well as a second axis coincident with the axis of the barrel and thus requires a complex movement and linkage to accomplish the disclosed functions. Accordingly, the device of the '617 patent falls short of providing an end effector for utilization over a large working span and for a wide range of applications. A surgical instrument with a rotatably mounted offset end effector, as disclosed in applicant's own U.S. patent application Ser. No. 08/847,252, discussed above, provides an important advance in permitting surgeons to perform such complex movements, over a large working span, and permitting multiple offset end effectors to be used. A problem associated with using multiple offset end effectors in a traditional endoscope having fixed point of view at the distal end of a rigid instrument is that the offset end effectors may swing into a position away from or blocking the endoscope view. This is especially troublesome in situations involving multiple end effectors used simultaneously. In such cases, the prior art endoscope provides a straight-on view from behind the end effectors and so cannot be used to directly view the entire end effector during a procedure, and so there is a need for a mechanism and method allowing visibility when using surgical instruments having rotatably mounted offset end effectors as disclosed in application Ser. No. 08/847,252.